1. Field of the Invention
The present invention relates to a substrate and a mask, and more particularly, to a device for aligning a substrate and a mask and a method using the same.
2. Discussion of the Background
As a type of flat panel display, an electroluminescent display can be classified as an inorganic electroluminescent display or an organic electroluminescent display, depending upon materials used for an emission layer. The organic electroluminescent display is attracting attention because it can be driven with a low voltage, have a low weight and be thin, have a wide view angle, and have fast response time.
A conventional organic electroluminescent display includes an organic electroluminescent device with an anode, an organic material layer, and a cathode, which are stacked on a substrate. The organic material layer includes an organic emission layer, which emits visible light by hole and electron recombination. Further, to transport the hole and the electron to the emission layer and enhance emission efficiency, an electron injection layer and an electron transporting layer can be interposed between the cathode and the organic emission layer, and a hole injection layer and a hole transporting layer can be interposed between the anode and the organic emission layer.
An organic electroluminescent device with this configuration can be fabricated by a physical vapor deposition method, such as a vacuum deposition method, an ion plating method, or a sputtering method, or by a chemical vapor deposition method using a gas reaction. The vacuum deposition method has been widely used to deposit an organic gaseous material on the substrate by evaporating an organic material in a vacuum. Such a vacuum deposition method employs an effusion cell to effuse the organic gaseous material evaporated in a vacuum chamber onto the substrate. Thus, the organic material layer of the organic electroluminescent device can be formed.
Recently, the size of the substrate has been enlarged for manufacture of a large-sized display. Accordingly, a deposition system has been developed to deposit the organic material layer on the larger substrate, where the effusion cell moves vertically in the vacuum chamber and effuses the organic gaseous material.
This deposition system includes a driving shaft to move the effusion cell vertically, and the driving shaft rotates about an axis by a driving means. As the driving shaft is rotated about the axis, the effusion cell moves vertically and effuses the organic gaseous material obtained by evaporating the organic material.
Further, to prevent a large substrate from sagging during the effusion of the organic gaseous material, a vertical aligning system of aligning the substrate with the mask in a standing state can be used.
Accordingly, a device for precisely moving the effusion cell applied to the vertical aligning system and an aligning method using the same are necessary.